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(No Model.) 2 Sheetsf-Sheet l. C. W. MEGGENHOFEN 8v A. S. GOURTRIGHT.

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(No Model.) 2 sheets-sheet 2.

C. W. MBGGENHOFEN vSv A. S; COURTRIGHT. BGRING MACHINE.

Patented Apr. 17.182,4.

WITNESSES mn. urHocnAPmNg caMFANY.

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l NITED 'STATES PATENT OFFICE.

CHARLES W. MEGrGrENHOFEN,l OF FRANKLIN, AND ALBERT SQCOURTRIGHT,

I OF INDIANAPOLIS, INDIANA.

BORING-MAcH-lNE.

SPECIFICATION forming part Of Letters PatentNO. 518,262, dated April 17, 1894. Application filed July 31, 1893. ySerial No. L1=3L968 (No model.)

duce a machine or auger by which holes of various shapes may be bored or out, such-as triangular, oval, elliptical or rectangular.

A machine or apparatus embodying said invention will be rst fully described and the novel features thereof then pointed out in the claim. v

Referring to the accompanying drawings which are made a part hereof, and on which similar letters of reference indicate similar parts, Figure 1 is a side elevation of a bit or auger embodying the principal features of our said invention; Fig. 2 a similar view from another side; Fig. 3 a central sectional view thereof; Fig. 4. an under side plan view, on an enlarged scale, of the cutting end of the bit or auger; Fig. 5 a transverse sectional view on the dotted line 5 5 in Fig. 3; Figs. 6, 7, 8 and 9 transverse sectional views at the points indicated by the dotted line 6 9 in Fig. 3; Fig. 10 a general View of a boring machine embodying our said invention, and Fig. 11 a general View of the same when operated by a common bit brace.

In said drawings the portions marked A represent the auger forming part of our invention; B a tube surrounding the same, and C rotary cutters mounted on the lower end of said tube. `rlhe auger or bit A isinmany respects of an ordinary form. As shown in Figs. 3 and 4, however, it is constructed to cut its borings or shavigsjn two parts, one of which is adapted to ascend. out of the hole upon one side thereof, and the other upon the other. The screw a is central, as is usual, and upon one side thereof is a narrow cutting bit a having a scoring bit a2 at its outer side, which cutting and scoring bits project below the outer ones, and are adapted first to outa narrow shaving or boring next the screw and send it up upon one side ofthe auger through or between one division of the conveyer flights thereof. The other cutting bit as is somewhat behind or higher up than the cutting bit a', and cuts the shaving or boring from 55 the point where the scoring bit c2 is located to the outside of the hole, where the scoring bits c4 are, and these shavings or borings ascend through or between the other opening or division between the conveyer iiights on 6o the auger.

- It is necessary, in order that the bit "shall enter the Wood, that the portion thereof bearing the conveyer iiights shall be considerably smaller than the cuttingportion, which must, of course, extend to the outside of `the hole being bored into which not only the upper portions but also the surrounding tube must enter. Cuttings or boringsof thefull size could not, therefore, ascend, and for this rea- 7o son they are divided, as above described. Just above the cutting portion of the bit or auger, and rigid therewith, is a collar or portion having cogs c, which, in effect, forma spur gear, by which the rotary cutters C are driven as the bit or auger is revolved, as will be presently more fully described.

The tube or sleeve B surrounds the con-v veyer portion of the bit or auger and extends down to near the lower end thereof, close to 8o the cogged portion. Its lower end has flattened sides, upon which the rotary cutters are mounted. It is held from revolving, in operation, by some suitable means, such as a transverse bar B', which is adapted to engage 8 5 in the case of the boring machinewith slide- Ways in the frame of said machine, as shown in Fig. 10, and in the case of a bit with the work being operated upon, as shown in Fig. 11,-rods B2 being shown as the means of en- 9o gagement,it being of course necessary that this partshould remain stationary, While the auger itself revolves. To relieve the strain upon the working parts, a' bearing A is secured to the auger shank, and extends down to and rests upon the upper end of this tube or sleeve B. This bearing is secured in place bya set screw S or otherwise. The cross bar B preferably consists of a hub and two arms, and is secured to the upper end of the sleeve roo B in any desired manner. The interior of the sleeve B necessarily comes in contact with the shavings or borings as they ascend from the cutting portion of the tube. We have found by experiment that if this interior is left smooth, such shavings or borings are apt to clog somewhat in their ascent, and we have found that this is corrected by rifling or grooving the interior ot' this sleeve, as shown most plainly in" Fig. 5.

The cutters C are practically small saws, and are secured to the flattened sides of the lower end of the sleeve B by short shafts ZJ thereon, which are preferably machine screws with fiat smooth heads, which pass through the central holes in said cutters, said holes being preferably countersunk for the reception of said [iat heads, so that there shall be no projecting parts to interfere with the operation of the tool, all as shown mostplainly in Fig. 3. Where there are four of these cutters, as shown in most of these views, two are of a diameter equal to the extreme diameter of the hole to be cut, and the other two are sufficiently less in diameter so that they pass between the edges of the other two, and thus all four sides of the holes are smoothly cut, the larger cutters operating to the extreme corners of such holes. These cutters have cogs by which they are driven, which cogs are in the shape of short spokes, swelled somewhat in the center where the cogs in the gear on the head of the auger come in contact therewith so that as the parts revolve they shall slide easily past each other. The form is illustrated in Figs. l and 2.

Wehave found that to use an ordinary mi` ter gear is impracticable, for the reason that the cogs will getchoked up with the cuttings or borings; but by making the cogs open or spoke-like, as we have done, this is obviated, and the device rendered practicable.

To bore a square hole, which is perhaps the semi-spherical in form, as shown.

In Fig. 8 is illustrated a construction where the hole is elongated, but still rectangular, and this result is secured by simply thickening two of the cutters.

An elliptical or oval hole could be secured by rounding all the cutters to the desired degree, and a triangular hole is secured by using three cutters instead of four, as shown in Fig. 9, all as will be readily understood.

Having thus f Lilly described our said invention, what we claimas new, and desire to secure by Letters Patent, is

The combination, in a boring machine, of an auger having a spur gear formed therewith or secured thereto, a surrounding sleeve, and a series of cutters mounted on said sleeve and provided with spoke-like open cogs engaging with and driven by said gear, whereby a hole corresponding to the shape of said cutters is produced, substantially as set forth.

In Witness whereof:` we have hereunto set our hands and seals, at Indianapolis, Indiana, this 15th day of July, A. D. 1893.

CHARLES W. MEGGENHOFEN. [L S] ALBERT S. GOURTRIGII'I. LL. s] Vitnesses:

CHESTER BRADFORD, JAMES A. WALSH. 

